Modeling and Analysis of Current Mode and V2 Controls with Adaptive Voltage Positioning (AVP) Design

Adaptive voltage positioning (AVP) is used in CPU application to reduce voltage spike during load transient. A lot of different methods have been proposed to achieve AVP function. In this paper, the active droop control are discussed and analyzed based on the advanced modeling techniques. With the accurate small signal model, the design guidelines are simplified for active droop control. Then the AVP design with constant on-time V ² control is given. The inherent DC offset of V ² control is analyzed under VR13 spec. A universal structure, which is modified from average current mode control, is given to solve the inherent DC offset of current mode and V ² controls. Simulation and experimental results show the good transient response, accurate load line and zero DC offset of the structure.